SPDIF > 802.3 Ethernet

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Hi all,

I would like to make a SPDIF to Ethernet converter. This would allow the digital output of a standard CD player (or players) etc to be streamed over a home network to one or more DACs.

SPDIF is a serial bit stream with biphase mark coding. The bit stream comes in with a baud rate just over 6Mbps (48Khz * 2 channels * 32bits per sample * 2 for BMC). The data rate is just over 3Mbps sustained.

The purpose of this is simple to take raw data from the SPDIF and wrap it up in a UDP packet for trasnmission over an ethernet interface. I'm not bothered about what's in the SPDIF data. I just want to move it from one meduim to an other (and back again at the other end).

I suspect that this is just too fast for an AVR even over the SPI interface if I had some external circuit removing the biphase coding.

Does anyone have any ideas on how to acheive this?

Regards,

Tim

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6 megabit per second is waaay to fast to do in software on an AVR. Or even 3!

Even if you have an ethernet hardeare interface, you would still need to pump data through at that sustatined rate. Not Easy!

Jim

Jim Wagner Oregon Research Electronics, Consulting Div. Tangent, OR, USA http://www.orelectronics.net

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Wait a minute... isnt that CD audio? 44100 samps/sec X 2 bytes per samp X 2 chan =176K bytes/sec. Avr can do that. Where did 6 megabits come from again? Thats 750 K bytes/sec... Avr can xfer ram to ram at 2 megabytes a sec, so maybe you could keep a 1 megabyte/sec (10 megabit/sec) ethernet full

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